(1) Field of the Invention
The present invention relates to a component mounting system such as a die bonder, or more particularly, to a frame feeding technology for fetching a frame from a frame cassette.
(2) Description of the Related Art
In a component mounting system such as a die bonding system (die bonder), a frame feeding system fetches a frame, on which one mount area or plural mount areas are formed, from a frame magazine one by one, and carries it to a work area. The component mounting system performs component attachment work such as die bonding, wire bonding, or bump bonding on the mount areas on the frame carried to the work area.
As mentioned above, for the component mounting system, the frame feeding system that fetches a frame from the frame magazine is needed.
FIG. 8A and FIG. 8B are diagrams showing an example of a conventional frame feeding system that fetches a frame stored in a frame magazine. In FIG. 8A and FIG. 8B, there are shown a frame magazine 801, a magazine lifter 802 that elevates or drives the frame magazine 801 (moves the frame magazine up and down (in Z-axis directions) at predetermined intervals), frame storage chambers 803 to 807, an upper part 808 of a loader feeder, claws 812 of the upper part 808 and a lower part 809, and the lower part 809 of the loader feeder. Also shown are a storage chamber unit 810 of the frame magazine 801, mount areas 831 to 833 formed on a frame, and frames 813, 814, 815, 816, and 817 each of which has the mount areas 831 to 833 formed thereon and which are stored in the frame storage chambers 803, 804, 805, 806, and 807 respectively. A circle 811 indicates part of the frame which the claws 812 clamps after being inserted into the frame storage chamber 803 of the frame magazine 801 in order to fetch the frame 813. Further, there are shown projections 843 and 853, 844 and 854, 846 and 856, and 847 and 857 each pair of which bears the frame 813, 814, 815, 816, or 817. The frames 813 to 817 are stored equidistantly at a loading pitch P that is a spacing in a height (Z) direction between adjoining ones of the frame storage chambers.
FIG. 8A is a cross-sectional diagram in which the frame magazine 801 is seen in a Y direction, and FIG. 8B is a diagram in which the frame magazine 801 is seen from a downstream X direction.
Referring to FIG. 8A and FIG. 8B, a conventional manner in which the frame feeding system feeds the frame 813 stored in the frame magazine 801 will be described below.
In FIG. 8A and FIG. 8B, one frame having mount areas formed thereon is stored in each of the frame storage chambers 803 to 807 of the frame magazine 801. In the storage chamber unit 810, as shown in FIG. 8B, the projections 843 to 847 and 853 to 857 are formed as partitions on the left and right sides (in the Y directions), and the center parts of the frame storage chambers 803 to 807 are spatially integrated into one. Therefore, the frames 813 to 817 are borne by the projections 843 to 847 and 853 to 857 respectively on the left and right sides in the respective frame storage chambers 803 to 807, and stored equidistantly. For convenience' sake, only a portion of the loader feeder that clamps the frame 813 and takes it out of the frame magazine 801 (the upper part 803, lower part 809, and claws 812) is shown, but a portion thereof that carries the frame, which a main feeder has delivered into a work area, is not shown.
A description will be made of a case where the magazine lifter 802 of the frame feeding system falls or moves downward (downward in a Z-axis direction), and lies at a height at which the frame 813 on the uppermost stage of the frame magazine 801 can be fetched.
The upper part 808 and lower part 809 of the loader feeder are moved in an arrow (1) direction (an upstream X-axis direction) so that the claws 812 can be advanced into an entrance part of the frame storage chamber 803. Thereafter, the upper and lower claws 812 are closed in arrow (2) directions (Z-axis directions) in order to clamp the frame 813. The loader feeder having the upper part 808, lower part 809, and claws 812 is moved in an arrow (3) direction (downstream X-axis direction) with the claws 812, which clamp the frame 813, held closed. Thus, the loader feeder takes the frame 813 out of the frame magazine 801, and carries it to a guide rail that is not shown.
At this time, as shown in FIG. 8B, since the frame magazine 801 has the projections 843 and 853 on the sides thereof, the claws 812 cannot advance to the left or right edge of the frame 813 and cannot clamp the left or right edge thereof. Therefore, the claws 812 have to advance to the center of the frame 813 (for example, the part indicated with the circle 811) so as to clamp and take out the frame 813.
However, the center of the frame 813 has the mount areas 831 to 833 formed thereon. Therefore, when the claws 812 are advanced to the frame storage chamber 803, the claws 82 come into contact with the mount area 831, 832, or 833. There is a fear that the mount area brought into contact with the claws may be damaged.
Therefore, it is necessary to largely reduce the sideways width in Y-axis directions of at least the claw 812 of the upper part 801. However, when the sideways width of the claw 812 is reduced, the frequency of a failure in fetching a frame or the frequency of a positional deviation of the fetched frame 813 increases.
Referring to FIG. 9, a conventional frame feeding method will be described below. FIG. 9 is a flowchart for use in explaining an example of an acting procedure in accordance with the conventional frame feeding method which is followed by a control unit of a die bonder.
At step S901, a loader magazine Z-axis motor (not shown) is controlled in order to move the frame magazine 801 so that a designated stage of the frame magazine can be aligned with the loader feeder (for example, the frame storage chamber 803 on the uppermost stage in FIG. 8A and FIG. 8B). The frame magazine 801 is then stopped.
At step S902, a loader feeder motor (not shown) is controlled in order to move the claws 812 of the loader feeder to the frame storage chamber 803 of the frame magazine 801.
At step S903, a loader feeder opening/closing electromagnetic valve (not shown) is controlled in order to close the claws 812 of the loader feeder so that the claws can clamp the frame 813.
At step S904, the loader feeder motor (not shown) is controlled in order to take out the frame 813 with the claws 812 of the loader feeder.
At step S905, a frame detection sensor (not shown) is used to detect presence or absence of the frame 813.
At step S906, if a decision is made based on the result of the detection by the frame detection sensor that the frame 813 is absent (Yes), the procedure proceeds to step S908. If a decision is made that the frame 813 is present (No), the procedure proceeds to step S907.
At step S907, the frame 813 is moved to a preformation stage.
At step S908, a buzzer and a revolving indicator such as a Patlite (registered trademark) are controlled in order to output information signifying that frame fetching has failed to cause an error.